1. Field of the Invention
The invention pertains to torque measuring tools in general and more particularly those which measure torque electronically using piezoelectric transducers.
2. Description of the Prior Art
Most known torque measuring tools or wrenches are mechanical. One well-known wrench uses a pointer attached to the wrench head. As the tool is turned deflection of the pointer away from the longitudinal axis of the wrench handle is measured on a visual scale. Another common torque wrench is capable of being preset to a given torque value. When that value is reached the tool produces an audible signal and further torque should not be applied. Some torque wrenches use strain gauges. An example is shown in U.S. Pat. No. 3,895,517. Another uses the alteration of resistance through carbon discs as shown in U.S. Pat. No. 2,174,356.